An Electronic Frontier Foundation audit of automatic license plate recognition systems released in late November revealed that police in Grosse Ile have scanned 8.41 million license plates in 2016 and 2017. The location data picked up by the readers was then shared with additional databases on request. Of those scans, 99.92 percent belonged to drivers not suspected of any crime.

In Grosse Ile, a stationary plate reader sits on each of the two roads leading on and off the island. The readers read 97 percent of all plates passing them, according to police chief Joseph Porcarelli. License plate data is stored for 72 hours, after which it is purged, according to township supervisor Brian Loftus.

The system read 8,410,004 plates during the audited time period. Of those, 6,509 plates matched vehicles associated with a criminal or civil violation.

Asked if he found the match rate to be too low, Loftus says that "since we are only attempting to match those plates under some level of investigation, I would propose that a 0 percent match rate would be optimum. We are an exceptionally safe community. [Automatic number-plate recognition] is one tool at our disposal to keep us that way."

A website for Vigilant Solutions, the makers of the Grosse Ile cameras, advertises that vehicles can be searched by plate number, year, make, model, or address.

There is no comprehensive national registry of automatic number-plate recognition (ALPR) systems available to the public, meaning that the crowdsourced EFF list — produced in cooperation with the journalism site MuckRock — is one of the most comprehensive audits citizens can view. While Grosse Ile is the only Michigan municipality mentioned in the EFF audit data, it is far from unique in its use of ALPR technology. A Metro Times query sent to a half-dozen large departments in Southeast Michigan received three responses. All three responses came from cities that use or have used ALPR systems.

According to Officer Douglas McCartney of the Ann Arbor Police Department, three readers were installed in parking enforcement vehicles and are mainly used to identify vehicles with lots of outstanding tickets. However, according to Eric Ronewicz, president of the Ann Arbor Police Officers Association, no one is currently trained to use the readers.

Sterling Heights Police Chief Dale Dwojakowski says a grant several years ago outfitted a single patrol car in each of six Macomb County departments with the technology, but adds that the system is no longer in use and that the city is looking at options for future ALPR deployments.

Meanwhile, in Detroit, ALPR systems are being used on parking enforcement vehicles in order to check whether parked cars have any open tickets on them. The technology is also coming to city parking garages, according to city spokesperson John Roach.

ALPR use is not restricted to Southeast Michigan. Police in Grand Rapids had already been using an ALPR system for four years by 2017, when The Grand Rapids Press wrote about a purchase of a similar system for parking enforcement.

Potential for abuse

In its dump of the ALPR data, EFF detailed what had been learned. The group put the nationwide count of license plate scans at 2.5 billion for the years 2016 and 2017.

"This unprecedented scale of data collection and sharing should alarm every driver on the road," the group states in text accompanying the release of the data. "The use of ALPR has created the digital equivalent of a massive police force keeping tabs on everywhere you go, potentially capturing information such as where you worship, what doctors you visit, and where you sleep at night. It also creates an enormous potential for abuse: We have long known that law enforcement officers abuse databases for personal reasons, such as spying on former spouses."

The EFF also found that while agencies may delete location data from their own repositories after a short period — as is the case in Grosse Ile — the data can live on for a much longer period in far-flung repositories where it is shared.

One example is the city of Coral Gables, Fla., where the New Civil Liberties Alliance is suing the municipality for access to records related to the use of plate-reading technology. While a lot is unknown in that case, NCLA attorney Caleb Kruckenberg says in an email to Metro Times that the city had been storing plate data for three years after its collection.

"ALPR data should only be stored as long as it remains necessary for a law enforcement purpose," Kruckenberg tells Metro Times via email. "It should be up to the state actor to demonstrate that a particular period of time is necessary. Certainly, the City of Coral Gables' storage of data for three years is well beyond an acceptable limit. Beyond that, it is certainly possible that very brief periods of time may be appropriate, but only to the extent that the state can articulate a legitimate need, which it can support with real evidence."

That legitimate need is key, since data could otherwise live forever on a server. Such a scenario is not entirely hypothetical, either: In China, dozens of local police agencies have purchased powerful facial recognition software that hangs onto data over the long term, flagging everything from jaywalkers to projected threats, in what Fortune magazine calls a real-world version of the "precrime" in Philip K. Dick's Minority Report.

"Sadly, we have every reason to believe that, without appropriate intervention by the courts, the Chinese view of surveillance is a preview of our own future," Kruckenberg says. "Indeed, nearly all of the arguments in favor of mass ALPR collection could be applied to CCTV and facial recognition."

"For example, proponents of ALPRs often argue that the information collected by the cameras has been put out into public view and so no one should object to its collection," he says. "If we are concerned about CCTV surveillance and facial recognition, we should be concerned about ALPRs as well."

"ALPR technology is not inherently unlawful, and could have legitimate law enforcement uses," he says. "However, the technology is extremely powerful, and must be carefully limited to protect core constitutional limits and the privacy of innocent citizens. NCLA's objections relate to the indiscriminate collection and sharing of data by law enforcement, even without particular suspicion of wrongdoing, and the collection and storage of large amounts of data for extended periods of time."

There are ways municipalities can make their systems more ethical, though there's disagreement on what that means. Michael Gerald, a business agent with the Police Officers Association of Michigan, recommends that data be stored for a relatively long extended period of time if it helps with long investigations. In at least two cities examined for this story, camera data is only retained for 72 hours, and sharing is only by request.

As a preemptive step, Grand Rapids has rules that require the police department to team with the American Civil Liberties Union to ensure that it is operating its plate readers in an ethical fashion.

Additionally, some states have taken the lead in regulating the way ALPR systems operate.

Michiganders hoping for a solution at the state level will have to wait, however: According to a list from the National Conference of State Legislatures, Michigan is not one of the 17 states that regulate ALPR systems on a statewide basis.

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